.header_top,
header .navbar-brand img {
  filter: grayscale(1);
}

.header_brand {
  background-image: none;
  background-color: #fff;
}

.header_menu {
  background: #4c4c4c;
}
.header_menu .main_nav .navbar-nav li.active > a,
.header_menu .main_nav .navbar-nav li:hover > a {
  background: #000;
}
#socials a {
  color: #fff;
}
.logo_text span,
.logo_text .text_vi,
.header_top ul li a {
  color: #000;
}